Vanity
by Fierceawakening
Summary: Some things that grew out of a prompt about characters' first times. I was prompted with "Knock Out/Sierra," and I'm picky about my xeno and Sierra's probably underage, so this is just snarky, somewhat flirty, non-explicit Decepticrack.
1. Chapter 1

"I'm sorry," a voice drawled, "but you're really not my type."

Sierra jumped back, staring at the red sports car in front of her with wide eyes. "Did you just talk?"

"Well, of course I did," it - _he, _from the sound of the voice - answered, his headlights flickering. "Really now, human, what did you take me for? One of those lifeless machines you drive?"

Sierra crept closer. Then, finding her courage, she put her hands on her hips. "No way! I'm not stupid, car. I figured you could _think._ I just never thought you knew how to _talk._"

The car's engine rumbled in what Sierra could only guess was an approximation of a snort. "And how, pray tell, did you figure _that_ one out?"

"Easy." She laid a triumphant hand on the car's red hood. "Nobody ever drives you."

The car's engine revved again, but this time it wasn't scoffing. It lurched forward, knocking Sierra off balance.

"Whoa - whoa there," she stammered, crawling backward. "You - you don't want to hurt me."

"The only reason I haven't run you over, skin job, is because it would take forever to clean off the mess."

Sierra scrambled to her feet and edged further away. This wasn't going well at all.

His headlights flashed again. "Keep your hands _off_ me, or I might just change my mind. After all, I'd need to clean myself after you touching me anyway."

Sierra shook her head. That motorcycle of Jack's wasn't nice either, not from the little she could tell. But she didn't think the bike would threaten to _kill _anyone. Maybe the bikes were the friendly ones?

"But - but look what I brought for you. Polish and - and wax!" She stumbled toward the items, grabbing for them and holding them up.

"Intriguing. But I still don't want you touching me. Just - leave them there, and I won't have to kill you."

Sierra edged closer again. "I don't have to touch you, you know. I've got cloths." She waved it at him. "See? Smooth. And if I put my hand in the middle of it, I can rub you with the wax or whatever, and you won't get any slime from my hands on your paint."

"Hm."

"You're interested." She grinned.

"I might be. But I'm going to have to kill you for knowing about me, either way."

Her grin widened. "No you're not. Then you'll have to find someone else to polish you. And I don't know what thinking cars do when they're not out street racing for fun, but -"

His engine revved again. Sierra froze, but he didn't move toward her. She heaved a sigh of relief.

"Believe me, human. You don't _want _to know."

Sierra carefully wrapped her hand in the cloth. That was as good as a yes.


	2. Chapter 2

Knock Out glistened.

He wasn't quite sure what his little pet got out of it all. Humans were, after all, tiny. And Sierra was a fairly small specimen anyway. She was female, and those tended to run small, and her body hadn't quite matured fully besides.

Polishing him to his satisfaction was exhausting even for other Decepticons. For his little human - well. He didn't like to imagine it.

Only that wasn't true. He liked it. He liked the disgusting, smelly perspiration that seeped from her - what were they again? Sweat glands? He liked the way it made her hair cling to her forehead. He liked the grumbling little exhausted gasps that came out of her vocal apparatus. He liked the way her hands slowed down, just enough to be irritating, just when she'd _almost_gotten it right.

He liked taunting her. "You missed a spot, skin job. I can't be seen anywhere like this." He liked revving his engine suddenly and lurching, knowing she was too fatigued to jump away.

Oh, he never actually hit her. As a rule, he didn't break his toys.

He liked that she knew it. He liked that she'd huff an answer, half-scoffing and half-gasping. "Come on, car. No one else is gonna do this like I do it. The others don't give a - a scrap - about your paint."

She was right, of course. No one else would do it as well. Not without a bribe. He'd stay. She'd laugh, another choked noise, running a free hand futilely through her sweat-damp hair. Then she'd go back to her work, smiling, tight-lipped with concentration.

It amused him, and startled him, and unsettled him, to realize just how much she seemed like one of his own kind at times.

But he couldn't puzzle out why she did it. No Decepticon would put such effort into helping someone else. Humans did that, humans and Autobots. Maybe she just did the things a human did. He didn't like that thought. It disappointed him.

One day, as twilight darkened the sky, every part of him gleaming but one tiny spot on his hood, he couldn't take it any more. "What's in it for you, fleshbag?"

Her hand froze in the middle of the circle it was tracing on his hood. "What do you mean?"

"I mean what the scrap are you doing? I work you until your hydraulics - er, muscles - can barely hold you up."

"You like to look pretty," she said, with a gesture he recognized as half of a shrug.

His engines purred. "I do. But that's not it."

She stared, her eyes widening. Then they narrowed, just the same as Starscream's optics did when he hatched some clever plan. "You go racing," she said. "Whenever you can get away. And you want to look good when you do."

"You knew that already," he answered, waiting.

"I want to race you," she said.

He shuddered, the vibration of his engine making her arm shake and her teeth rattle. "Don't make me kill you, human. You're too amusing for that. It would be a waste."

She smiled. "Take it easy, car. I didn't say I wanted to drive."


End file.
